One of the common tropes one hears from advocates of confidence intervals is that they are superior, or should be preferred, to p values. In our paper "The Fallacy of Placing Confidence in Confidence Intervals", we outlined a number of interpretation p...
One of the most common tasks in statistical computing is computation of sample variance. This would seem to be straightforward; there are a number of algebraically equivalent ways of representing the sum of squares \(S\), such as \[ S = \sum_{k=1}^n (...
Teaching undergraduate psychology is difficult for a variety of reasons. Students come in with preconceived notions about what psychological research is and are sometimes disappointed with the mismatch between their preconceptions and reality. Much of ...
Suppose you are reading a paper that uses Likert scale responses. The paper reports the mean, standard deviation, and number of responses. If we are -- for some reason -- suspicious of a paper, we might ask, "Are these summary statistics possible for t...
As of January 1, 2016, I am the new methods editor for the Psychonomic Society digital features. Steve Lewandowsky has written an introductory post with a bit of background, and my first post -- about Arsenault and Buchsbaum's recent article in Psychon...
In my last post about standardized effect sizes, I showed how averaging across trials before computing standardized effect sizes such as partial \(\eta^2\) and Cohen's d can produce arbitrary estimates of those quantities. This has drastic implications...
Recently, there have been many calls for a focus on effect sizes in psychological research. In this post, I discuss how naively using standardized effect sizes with averaged data can be misleading. This is particularly problematic for meta-analysis, where differences in number of trials across studies could lead to very misleading results.There are two main types of effect sizes in typical use: raw effect sizes and standardized effect sizes. Raw…
Over at the Psychonomic Society Featured Content blog, there are several new articles outlining some of our work on confidence intervals published previously in Psychonomic Bulletin & Review. In a three-part series, Steve Lewandosky ...
As of yesterday, our paper outlining the PRO Initiative for open science was accepted for publication in the journal Royal Society Open Science. It marks the end of many tweaks to the basic idea, and hopefully the beginning of a new era in peer reviewi...
This post is related to my open science talk with Candice Morey at Psychonomics 2015 in Chicago; also read Candice's new post on the pragmatics: "A visit from the Ghost of Research Past". In this post, we suggest three ideas that can be implemented in ...
